Refurbishing a micro-hydro installation at Châtel
An ambitious refurbishment project was carried out by HYDRO’s teams. To perform the task, the engineers had to innovate and deploy new technologies.
The local municipalities forming the Communauté de Communes des Pays d’Evian-Vallée d’Abondance (CCPEVA) turned to HYDRO Exploitation to refurbish worn and obsolete components in the micro-hydro installation at a drinking water reservoir. Located on a mountain pasture in the municipality of Châtel, the reservoir is not connected to the electricity grid. Its monitoring, control and water treatment equipment is powered locally by a microturbine combined with a bank of batteries. HYDRO was the only company with the multidisciplinary skills needed to provide this specialist service.
3D printing
The work involved replacing the original bronze Turgo wheel had to be replaced. This was in a bad state and HYDRO had to be bold to solve the problem. Because foundry suppliers were unable to produce such a small part, the engineers had to work with a Swiss specialist in 3D printing to create a new prototype of the wheel in 316 stainless steel that offers optimum resistance to wear.
Electrical challenge
The electrical part of the project also presented challenges. The team had to find a compact 48 VAC three-phase alternator with permanent magnets, and design and assemble an electrical cabinet including the battery bank charging converter (12 VDC), an energy diverter with resistors to evacuate excess energy, and an inverter supplying the end users with 230 VAC single-phase. The equipment had to be configured to ensure correct adjustment of the turbine speed and battery voltage. Finally, the installation was tested on HYDRO’s premises before commissioning on site.
